iCallID is the returned ID of the service call. In case of asynchronous call, this ID should be matched with the ID returned as a property of the result object. Only when matched can the result object be associated with this service call.

sFriendlyName is the friendly name associated with the Web service. Call the useService() method to assign a friendly name to your Web service. See Page 6 for details.

oCallHandler is the callback handler function for processing the result object. This parameter is optional.

funcOrObj is either the Web service's method you want to call, or the call options object. You can set this object with the createCallOptions() method (see Page 5 for details). You don't have to set all nine properties, but be sure to set its funcName property to the Web service's method you want to call. If not set, WebService won't know which Web service's method to call. This parameter is required.

oParam are a comma-delimited list of parameters that the Web service's method expects. This parameter is required.

The following example shows a call to callService() without the first, optional parameter: